Robert von Welz (15 December 1814 in Kelheim – 12 November 1878 in Würzburg) was a German physician and ophthalmologist.
From 1832 he studied sciences and medicine at the University of Würzburg, receiving his medical doctorate in 1838. For several years he worked as an assistant physician at the Juliusspital in Würzburg, then in 1849 traveled to Paris, where he conducted research of syphilis. In Paris he became engaged in a dispute with Philippe Ricord in regard to the transferability of syphilis. His interests later turned to ophthalmology, and in 1854/55 he studied the subject with Albrecht von Graefe in Berlin. In 1857 he opened an eye clinic in Würzburg, and in 1866 he was named a professor of ophthalmology at the university. At the time of his death, the eye clinic was acquired by the University of Würzburg.
He was known for his development of various medical devices, such as an apparatus for the inhalation of ether and an instrument used for enucleation.